Class B roof assemblies are effective against which level of fire-test exposure?

Class B roof assemblies are designed to be effective against moderate levels of fire-test exposure. This classification means that such roofs can withstand specified fire tests for a certain amount of time, providing adequate protection against flames and heat from potential fire sources. The performance of Class B roofs indicates that they have better fire-resistive properties compared to lower classifications, while still not reaching the rigorous standards that Class A roofs meet.

In commercial buildings, fire safety is a critical aspect of construction and design, and Class B roofs are often chosen for structures where moderate fire exposure is a likely risk. This makes them suitable for various applications, striking a balance between cost-effectiveness and fire safety without being excessively high in fire resistance.

Understanding this classification helps inspectors evaluate building safety and adherence to fire codes, ensuring that appropriate materials are chosen based on the building's location and use.